We are currently choosing the UI technology to write a new Excel Add-in in our firm. Quite a lot of the team has a background in WPF and given the ability to test the components as they are built would be preferable. However, I noted from your release notes and a few of the forum posts that there is an incompatibility between WPF and Office applications in general.

We intend to build an Excel add-in that makes use of a side panel to drive user input to cells and perform data retrieval from a web service.

Actually, we now have only one WPF-related issue: a WPF context menu or the dropdown part of a WPF combobox may collapse immediately after you expand it; this may occur if the control in question is located on an Add-in Express pane. We've provided a workaround for this issue; check the sample project at http://temp.add-in-express.com/support/WpfPopupWorkaround.zip. We haven't invented a decent way to incorporate this workaround in the code of Add-in Express.

Gavin Howard writes:
There is also a recurring link to, I'm guessing, the issue you have logged with MS on the issue:

That link described another issue: if you expand a context menu or the dropdown part of a combobox and then click in the host application's window, the control may state expanded; this may occur if the control in question is located on a Custom Task Pane. This issue wasn't started by us so we don't know its current status. I haven't been able to reproduce it in Excel 2016 on a custom task pane shown by an add-in built using .NET Framework 4.X.

This technology is now available for our custom development services only. Based on the Add-in Express for Office core, it is designed for building custom-tailored Office add-ins with far less coding than you usually have to do. Plus, it includes all Add-in Express features such as True RAD, visual designers, Outlook view and form regions, etc.

Get the best platform for building version-neutral, fast and easy deployable plug-ins by using Add-in Express projects templates, visual designers, components and wizards in combination with a perfect Delphi compiler.

This is an extension for Visual Studio that allows developers to quickly create WiX-based setup projects in a familiar Visual Studio way.

The Designer for WiX Toolset lets you forget the plain Windows Installer XML and concentrate on your deployment logic. It integrates several editors with the Visual Studio IDE and provides a set of vdproj designers to configure the file system, registry, user interface, custom actions, launch conditions and more for your setup projects.

The innovative technology for customizing Outlook views and forms. It is included in all Add-in Express for Office products and can be used to extend Outlook views, e-mail, task and appointment windows, To-Do bar, Reading and Navigation panes with your own custom sub-panes.

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